Incandescent electric lamp.



W. R. WHITNEY. INCANDESGBNT ELECTRIC LAMP.

APPLILATION ILED ACG. 19. 1907.

RENEWED SEPT.23,1910.

Patented May 9, 1911.

I/.VTNLSEES' JMVENTH l/IZILLJS H. WHITAEX E Y l ATTYT A 991,578. iApplication tiled August 19, 1997', Serial No. 338,311.

WILLIS R. WEITNEY, SCHENECADY,VNEW' XOEK, JAS-SIGNOR CEO GENERAL"ELEC'ERC CQMPAY, ,CQEEORATI-QN 0F NEW YORK.

NCANFESCENT ELECTRC LAMP.

lTo all whom it concern:

Be itknown that I, lVinLis YinTni-r,

.a citizen of the United States, residing at Schenectadyg county ofSchenectady, 'State of New York, have invented certain new and usefulimprovementsl 1n incandescent ElectricLamps, lof which the following isa. specification.

My present invention relates to incandescent lamps and comprisesineenstor holding thec filament or filaments in position in the lampbulb.

Tungsten, molybdenum, tantalum, fand' .similar refractory elements nowbeing. use d for incandescent lamp filaments have a tendenoy to becomesoft and plastic Wlieiiheatv ed to high incandescenceJ and filaments oithese materials must ordinarily be anchored OI S11 ported Within thelamp bulb in order that eformation and destructionof the ti1ament maynot result when the iilainent is hot and soft.

-'Tl1e 'novel' features of my invention are particularly pointed out .inthe appended claims, and for better understandinr thereof, referenceshould be had to the ollcwing description taken in connection aivitlithe accompanying drawing.

. In the drawing, thencandesoent lamp l 1s provided witha'-stem2-l1aving-suitable g supplyl Wires connected with a refractoryfilament 4 of tungsten or other material having a tendency tion. Thelamp stem 2 is provided with a toA sagduri-ng normal operayliidricalglass pedestal 5 projecting up- Ward along the axis of the lamp andserving to support the glass tube-cap 6. This tube-,cap 1s movablelongitudinally."along" spring of carbon, as shown in the drawing. Theannular tube-cap carries,

refractory. material inert the filament 4.

When thelamp is assembled, thecarbon with respect to spring 7 iscompressed somewhat by` pushof the filament 4,

andpooling or otherwise, may occurwithoat Specification of Lettersatent.`

vinto a spiral before baking.'

filament, .a

Y longitudinally. on said .st-em,

at its closed end, a filament .support 8 of tantalum, or other .metal.lamenn means power of said spring to during normal heating Patented May9, itil, Renewed September 23, 19m. Serial No.

materially changing' `the tension .under spring l l The spiral springordinary carbon lamp filaments .are made, except, hotter/er, that itshould be Wound Such a spring iose its .resilient qualities 'when whichtlieiilament is subjected by the spiral does not subjected ment isadequately protected from contamination Awith carbon orvother material:from the resilient support-ing means; i i have illustrated vmy inventionas applied to a low voltage or series' lamp, but obviously this spiralspring arran ement could easily ne applied to ,a multipleglament lamp bymerely adding additional filament supports'8.

What l claim as new and desire to secure by Letters Patent of the UnitedStat-es, is,"

i. rEhe. combination ot a refractory metal resilient carbon supporttherefor, and protective means interposed between said -lament and saidsupport.

` 2, The combination onta refractory metal lil-amont, supporting meansengaging there-r with, and a carbon spiral for' resiliently supportingsaid means.

3. 4The fcombination Aoa lamp stem, a pedestal thereon,

a tubular cap .movable l a spiral Vspring inclosed by said cap andengaging with said may be made much as,

to t-lielieat of the lamp. By the .arrangement described, the tungstentile:

stem, and -iilament supporting means carried by said ca 4. Thecombination of a carbon spiral, a

refractory metal filament, and means for holding said spiral undercompressionyfand for holding said filamentunder tension.

5. The combination of spring, means for applying the power of saidspring to hold the metal filament under tension, and' va glass spring.6. 'The combinationy of envelop inclosing said a carbon spring, a forapplying the hold the filament under tension, and, means for protectingsaid filament from Vcontamination Aby -said carbonspring. i

spiral carbon 7. The 1 combination iaith refractory i metalflamentgof aresilientcarbon member for. supporting said alanient suitatle

